My other 18650’s (AW 2200 mAh) don’t get as nearly as hot or cause the charger to get as hot. I usually run them past 3.5 before charging. My 3 Eagletac Red Tops 3400 mAh 18650s in the Thrunite TN41 don’t get hot either (but warm). It’s probably is time for a new charger for the samsung 30Qs… .